Propagation of a spherical detonation wave in an expanding, gravitating universe

The question of whether primordial perturbations are initially able to grow in a detonation regime is addressed. It is shown that a similarity solution obtained to describe shock-wave propagation in an expanding early universe can be extended to the case of a detonation (blast) wave. If the adiabatic index kappa is greater than 1 and less than kappa1 (kappa1 is between 1.2-1.21), a continuous solution will exist throughout the flow region from the center to the wave front with a discontinuity across the characteristic surface. If kappa is greater than 4/3, a shock will develop in the flow behind the detonation front. If kappa is greater than kappa1 and less than or equal to 4/3, no physically admissable similarity solution will exist. 8 references.